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Anchor Worms prevention and identification. Please feel free to send any comments or suggestions to Ask An Expert.

This is a parasite that is extremely rare in aquarium fish. It is a copepod. It must be brought in by an infested fish. It is usually found in ponds. The head of the worm is anchored into the fish's skin.

Anchor worms were highly contagious and that they are not actually worms, but a freshwater copepod. Only the female will attach itself to the fish, underneath a scale usually deep into the muscle tissue with its powerful extensions on the sides of its anchor shaped head (hence the name anchor worm). The male lernaea will then attach himself to the female’s body. The female will produce egg sacs fertilized by the male, which are then released into the water column. The eggs hatch into a free swimming larvae or nauplii. This is the stage where the crustacean will attach to the fish completing the life cycle. After releasing the eggs, the parents will die off leaving a gaping wound, which is highly susceptible to secondary infections.

Anchor Worms Treatments

Potassium permanganate dip at 100mg/2.5 gallons of water, or

Salt dip

Formalin dip at 2 to 4 ml Formalin/2.5 gallons of water for 30 minutes, the fish may lose equilibrium and must immediately be transferred to clean, fresh water

Modern antiparasitics (such as Disco-worm, Fluke tabs, and Clout) may help

Salt in the aquarium at 1 to 2 tablespoons may help prevent secondary infections

The best treatment is to remove them by hand and quarantine the tank. You may have to do the following a few times. Tweezers work well for removing the anchor worms, try to grip them as close to the wound as possible. Pperiodically dunk the fish into the bucket of water to let him get a few breaths before continuing. After removing as many as you can see, use stress coat and pray.

Anchor Worms Prevention

Really the only way to get this is to bring it in from somewhere else, Local Fish Stores that are infected. Be sure to quarantine all new fish and never risk your established tank fish! Also remember to use any and all precautions necessary to protect you and your fishy friends when working with harmful chemicals.